title: To feed or not to feed: plant factors located in the epidermis, mesophyll, and sieve elements influence pea aphid's ability to feed on legume species.
abstract: The pea aphid (Acyrthosiphon pisum Harris), a legume specialist, encompasses at least 11 genetically distinct sympatric host races. Each host race shows a preference for a certain legume species. Six pea aphid clones from three host races were used to localize plant factors influencing aphid probing and feeding behavior on four legume species. Aphid performance was tested by measuring survival and growth. The location of plant factors influencing aphid probing and feeding was determined using the electrical penetration graph (EPG) technique. Every aphid clone performed best on the plant species from which it was originally collected, as well as on Vicia faba. On other plant species, clones showed intermediate or poor performance. The most important plant factors influencing aphid probing and feeding behavior were localized in the epidermis and sieve elements. Repetitive puncturing of sieve elements might be relevant for establishing phloem feeding, since feeding periods appear nearly exclusively after these repetitive sieve element punctures. A combination of plant factors influences the behavior of pea aphid host races on different legume species and likely contributes to the maintenance of these races.
authors.affiliation: Department of Biochemistry, Max Planck Institute for Chemical Ecology, Jena, Germany.
authors.forename: Alexander
authors.initials: A
authors.lastname: Schwarzkopf
authors.forename: Daniel
authors.initials: D
authors.lastname: Rosenberger
authors.forename: Martin
authors.initials: M
authors.lastname: Niebergall
authors.forename: Jonathan
authors.initials: J
authors.lastname: Gershenzon
authors.forename: Grit
authors.initials: G
authors.lastname: Kunert
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001042:Aphids / Q000502:physiology*; D004553:Electric Conductivity; D005060:Europe; D007887:Fabaceae / Q000737:chemistry* / Q000469:parasitology*; D005247:Feeding Behavior / Q000502:physiology*; D058503:Mesophyll Cells / Q000737:chemistry; D019441:Plant Epidermis / Q000737:chemistry; D013045:Species Specificity; D055549:Volatile Organic Compounds / Q000032:analysis
chemical_list: D055549:Volatile Organic Compounds